Encode text and files to Base64 or decode back with full Unicode and URL-safe support, line-break control, and instant validation for developers offline.
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Quick answer: Base64 Encode / Decode — Encode and decode Base64 text Free, no signup, runs in your browser. See below for the interactive tool, 4-step guide and FAQs.
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No. Base64 merely repackages bytes into readable characters, offering zero confidentiality. Anyone pasting aGVsbG8= instantly recovers Hello, so concealing mango123 as encoded text remains trivially reversible. Treat it as transport armor for email and JSON, never as secrecy. For genuine protection, employ password-based AES at /aes-encryptor with robust keys.
Yes. Characters first map to UTF-8 bytes, so accents, emoji, and twelve scripts survive round trips. For example, Hello becomes aGVsbG8= with single pad, decoding restores Hello exactly, while a 50KB note with 800 emoji lines converts within a second. All processing stays inside this tab. No upload occurs.
Yes. Enable URL-safe variant per RFC 4648, where and turns to minus and slash turns to underscore, with padding stripped for links. For instance, bytes fa fb fc render as and vv8 standard but minus vv8 safe for query strings. Apply it to JWT segments, filenames, and identifiers. Line wrapping every 76 characters suits legacy mail gateways handling long payloads.
Growth stems from mapping three input bytes onto four six-bit characters, adding thirty-three percent overhead and padding. A 30KB icon swells near 40KB text, while 90KB payloads approach 120KB. Chunked line breaks inflate further. Budget storage accordingly, prefer raw binary for bulk archives, reserve Base64 for JSON, XML, and mail where textual safety outweighs verbosity.
Base64 translates raw bytes into capital letters, lowercase letters, digits, plus, and slash so mail systems and JSON conduits transport binary without corruption. Example 1: type Hello, receive aGVsbG8= with one pad, paste aGVsbG8= back to recover Hello exactly. Example 2: transform a 30KB icon into roughly 40KB characters for inline embedding inside stylesheets during prototypes. Grouping packs three bytes into four characters, inflating volume by thirty-three percent, a tradeoff accepted for textual safety. Developers shuttle images through APIs, obscure binary in logs, and prepare data URLs for demos. Accented names survive because UTF-8 bytes encode before mapping, preserving multilingual content across boundaries with consistent round trips for teams. Validation rejects stray spaces, missing pads, and foreign symbols, prompting cleanup before decoding attempts proceed smoothly.
Input text first converts to UTF-8 byte sequences, ensuring cafe with five letters occupies six bytes while emoji consume four bytes apiece. Padding with equals signs completes final quartets: Hello spanning five bytes closes with one pad, Hi spanning two bytes closes with two pads in classic implementations. Reference alphabet table: standard 62 is and | standard 63 is slash | URL-safe 62 is minus | URL-safe 63 is underscore | pad is equals stripped in safe mode | line wrap every 76 characters for mail. Edge case: fa fb fc bytes encode as and vv8 standard versus minus vv8 safe, so copying wrong variant breaks JWT verification. Always select matching mode before pasting tokens into validators to avoid false failures during integration.
Encode Hello to obtain aGVsbG8=, decode aGVsbG8= to confirm Hello returns, then test cafe to watch multi-byte expansion firsthand. Second demonstration: encode a 12KB PNG, assemble data image PNG Base64 prefix and characters into an image tag for disconnected previews. Limitation: encoded output inflates size, exposes content to trivial decoding, and struggles with multi-megabyte binaries that stall modest devices. Unlike the image converter at /image-to-base64 which optimizes file uploads and previews, this utility centers on typed strings and URL-safe tweaks. For file-centric workflows, see the converter at /image-to-base64 for drag-drop handling. Very long outputs benefit from 76-character wrapping for mail, while JWT parts demand unwrapped safe alphabets without pads for successful authentication. Validate lengths before embedding to prevent truncated rendering across strict gateways.